About M12 connector development overview

Since its inception in 1985, the M12 connector has grown into the interconnection system of choice in the industrial automation field. This kind of sturdy and durable connector can achieve reliable connection in the harshest environment, thus bringing an innovation to the connection technology in the field of industrial automation.

The M12 connector is a circular connector with a 12 mm locking thread, and generally has an IP protection level to prevent liquid and solid intrusion. M12 connectors are ideal for sensors, actuators, industrial Ethernet and fieldbus devices, and are mainly used in industrial automation and corrosive environments.

Before the M12 connector was developed, engineers either had to directly pull the cable, or had to repeatedly replace the connector due to poor use conditions. The initially released M12 connectors are 3-pin and 4-pin models. Although they are inferior to its predecessor, the RK30 connector, in terms of the maximum current allowed to flow, it can provide IP67 protection. The 4-pin M12 connector allows a single system to incorporate more advanced sensors and actuators. Nowadays, such sturdy and durable connectors are divided into 3-pin, 4-pin, 5-pin, 8-pin and 12-pin configurations, and various new locking methods such as bayonet and push-pull are continuously developed.

In addition to factory automation, M12 connectors and M12 cable assemblies can also be used in measurement and control, communications, transportation, robotics, agriculture, and alternative energy fields. The correct selection of the number of pins depends on the specific application requirements-3-pin and 4-pin models are used for sensor and power applications; 4-pin and 8-pin models are used for Ethernet and PROFINET; DeviceNet and CANbus generally use 4-pin and 5-pin M12 Connector; 12-pin models are usually used for various signal applications.

In addition to the different number of pins, the M12 connector also uses a variety of key positions to prevent incorrect mating. The most commonly used encoding types and their uses are listed below:

l A code: sensor, direct current, 1G Ethernet

l B code: PROFIBUS

l C code: alternating current

l D code: 100M Ethernet

l X coding: 10G Ethernet

l S code: alternating current (to be replaced with C code power components)

l T code: direct current (a code power component will be replaced soon)

The most popular M12 encoding types are A encoding, B encoding, D encoding and X encoding. A code, B code and X code are some of the M12 connectors that have been developed the earliest and have the longest time to market. In the field of high-speed industrial Ethernet, the demand for X-coded connectors continues to grow, and will eventually replace A-code and D-code components in Ethernet applications. The latest M12 code types currently under development are K code for AC power and L code for PROFINET DC power.